Necrotizing sarcoid granulomatosis: a rarity in childhood.

Necrotizing sarcoid granulomatosis (NSG) is characterized by pulmonary nodular infiltrates, a typical histology, and a benign clinical course. The etiology and pathogenesis of the disease are still unknown. In childhood, it is extremely rare, with only three reported cases so far. Here we report on an 8-year-old girl, who to our knowledge is the youngest reported patient with NSG. The girl presented with shortness of breath and a sore throat. Chest X-ray and computed tomography (CT) scan revealed multiple nodular opacities of the lung. The symptoms and radiological findings disappeared within 6 months without any treatment. The diagnosis was based on the typical signs and symptoms of NSG and on the exclusion of other diseases. As abnormal immunological findings such as the lack of specific diphtheria antibodies in spite of vaccination against diphtheria were present, we suggest that immunologic mechanisms could play an etiologic role in the pathogenesis of NSG. In addition, the ratio of CD4+/CD8+ T-cells in the peripheral blood was significantly reduced, whereas the CD4+/CD8+ T-cell ratio in the immunohistochemical staining of the lung tissue was elevated. Since this compartmentalization is a typical finding in sarcoidosis, it supports the theory that NSG may represent a variant of sarcoidosis. However, because some characteristics of NSG are uncommon in typical sarcoidosis, NSG may also be an entity in its own right.